Search for Bulk Motion in A2256 with Suzaku and ASTRO-H UEDA Shutaro, HAYASHIDA Kiyoshi, NAGAI Masaaki, and TAWA Noriaki (Osaka University) August 19-21,2010@Minakami Onsen

What is Abell 2256? Optical image of Abell 2256 Briel,U.G. et al. 1991 Fusco-Femiano, R. et al. 2005 Rephaelo, Y. & Gruber, D.E. 2003 XIS image of Abell 2256 XIS0 0.4-10keV 0.5Mpc sub main Optical image of Abell 2256 (http://www.astr.ua.edu/white/mug/cluster/a2256.html) A2256 is one of the most extensively studied merging clusters with distinctive two peaks (main and sub) near the center1). A2256 is also one of the clusters in which non-thermal hard X-ray emission was detected with Beppo-SAX 2) and RXTE 3). We have examined redshift difference of the hot gas in the main and sub clusters in A2256.

We measured the redshift of He-like Iron line by using APEC model. Suzaku Observation Ueda et al., 2010 in prep We measured the redshift of He-like Iron line by using APEC model. MWH LHB CXB ICM Fig. 1 Spectrum of Main-Cluster Fig. 2 Spectrum of Sub-Cluster kT=7.33+0.13-0.14keV Z=0.30+0.02-0.02 kT=6.20+0.11-0.06keV Z=0.31+0.02-0.02 We found the redshift difference of 0.342+0.189-0.215 x10-2 between two regions. Main XIS0 XIS1 XIS3 Weighted mean Chandra Sub Optical galaxies Fig. 3 Redshift difference between　the main and sub clusters Optical galaxies (Berrington et al. 2002) Chandra (Sun et al. 2002)

Fig 4 : XIS spectrum in 6-8keV range Fig 5 : SXS spectrum in 6-8keV ASTRO-H Simulation We performed SXS simulation based on the spectra fit results with Suzaku XIS. The exposure time of 78ks is assumed. The SXS Count rate is ~0.4cts/s in the entire band and 2.2x10-3 cts/s in Fe-K lines. Suzaku XIS Fig 4 : XIS spectrum in 6-8keV range SXS Simulation Fig 5 : SXS spectrum in 6-8keV Redshift [ x10-2 ] main sub XIS 5.972+0.166-0.164 5.630+0.090-0.139 SXS 5.974+0.005-0.005 5.634+0.002-0.007 Velocity Difference [km/s] 1025+566-644 1022+10-25 The redshifts of the hot gas in the main and sub clusters will be measured with accuracy of tens of km/s by using ASTRO-H SXS, when we ignore the turbulent flow. Further SXS simulations in which turbulent flow is considered are presented in the poster. Table 1 : Redshift obtained with XIS and SXS